1. Field
The present invention relates generally to automatic shutoff valves and improvements thereof. More particularly, the present invention relates to earthquake triggered shutoff valves capable of electric control and improvements thereof.
2. Description of the Related Art
Earthquakes can pose significant problems not only to the structural integrity of a building exposed to such seismic activity, but also increases the potential risk of damage to piping systems, fixtures, or appliances located throughout the structure. These risks are particularly dangerous when such systems, fixtures or appliances utilize flammable gases or fluids that may begin to leak upon a seismic event. A rupture of a natural gas pipe or feed line due to earthquake activity greatly increases the risk of fire or explosion if the flammable gas or fluid flowing through the pipe or feed line is allowed to continue flowing despite the damage to its piping system. In an effort to mitigate these risks, earthquake sensitive gas shut-off valves have been used for automatically preventing the flow of gases or fluids through the valve once the valve is acted on by a particular level of vibrational force.
However, current systems have several potential drawbacks that limit their usefulness or desirability for many users or applications. As society increasingly utilizes computers or electronic-based safety or monitoring systems for building maintenance or control, standard earthquake triggered shutoff valves have proven difficult to incorporate or integrate within the electronic safety systems already in place or to be installed. Indeed, current earthquake sensitive gas shutoff valves are typically utilized as an additional back-up system in the case of a natural disaster and may not be incorporated for monitoring or control within the context of the overall electronic safety or control system for a structure. Before the computerization of building safety systems, such a mechanical-only solution posed no additional inconvenience since the remaining system components were also mechanical in nature. However, with the advent, popularity and convenience of computerized safety systems, it has become desirable for every device operating in the safety system to be capable of monitoring or control by the electronic system. Earthquake triggered valve systems that do allow for some form of electronic control functionality require the provision of external power to the valve in order to power the electrical components within for closing or opening the valve. Such valves are inadequate for use when power has been lost at the facility as can easily occur during a seismic event and thus fail to operate as may be required.
Thus, a vibrational force sensitive shutoff valve is desired that can be easily integrated into an electronic monitoring or control system. The vibrational force sensitive shutoff valve would desirably be cheap to manufacture and capable of operating automatically upon an earthquake or via electronic control. It would be desirable for the shutoff valve to operate without requiring external power for powering its electronic components and could be electronically controlled either automatically by a connected safety system or by manual direction from a user.